Experimental Evidence of the Correlation between Possible Precursors of Earthquakes in Near Surface Quasistatic Electric Fields and in the Ionosphere

  1. Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radowave Propagation, Russian Academy of Sciences
  2. Institute of Space Physics Research and Radiowave Propagation, Far East Division, Russian Academy of Sciences

We consider data obtained when the parameters of the ionospheric Es and F2 layers and the vertical gradient of the electric potential in the surface atmosphere were simultaneously measured during the preparatory period of crustal earthquakes with M = 5.0–6.2 in the Kamchatka region. The appearance of anomalously high Es, accompanied by an increase in frequency parameters of the sporadic layer and the regular F2 layer, was detected on days when possible earthquake precursors, as determined earlier, occurred in atmospheric electric fields. The presumed earthquake precursors in the ionosphere are divided into two groups with different earthquake lead times ranging from several hours to two weeks. Empirical dependences are presented that connect the lead time of an earthquake (from the moment of the appropriate anomaly’s occurrence in the ionosphere or in the atmospheric electric field to the moment of the shock) and the epicentral distance to the observation point with the earthquake magnitude. These dependences are different for the two groups of presumed earthquake precursors, but they are close inside each group of possible precursors isolated on the basis of quasistatic electric field measurements and revealed in ionospheric parameter variations.

DOI: 10.1134/S0016793210070157

 

Korsunova L.P., Mikhailov Yu.M., Khegai V.V., Leshchenko L.N., Smirnov S.E. and Bogdanov V.V. Experimental Evidence of the Correlation between Possible Precursors of Earthquakes in Near Surface Quasistatic Electric Fields and in the Ionosphere. // Geomagnetism and Aeronomy, 2010, Vol. 50, No. 7 (Special Issue 1), pp. 920-926